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Crinkled french fries, discarded receipts, old gum wrappers  you probably have everything in the hidden corners of your vehicle except great bass. ThunderForm enclosures fill the nooks and crannies of your vehicle with low tones that stand out, but their factory look blends right in.

MTX engineers evaluate the "sonic signatures" of top-selling vehicles so they can design ThunderForms as custom acoustic matches. Each ThunderForm fits and blends inconspicuously into your vehicle, so you get great bass without losing any space. The high-density polyethylene resin enclosure curbs unwanted resonances from your sub, so you'll hear bass that's tight, hard-hitting, and way down low.

This molded MTX ThunderForm comes loaded with a premium-quality 10" Terminator subwoofer and a specially-designed amp that puts out 200 watts RMS. It installs under the rear seat of your 2009-up Ford F-150 SuperCrew with no loss of leg room. MTX's Electronic Bass Control (EBC) lets you adjust the bass level from the driver's seat. Hardware and harness are included.

Product Highlights:

custom-fit powered subwoofer

enclosure fits under rear seat

one 10" Terminator subwoofer

built-in 200-watt RMS Class-D amplifier

high-density polyethylene enclosure

variable low-pass filter (50-150 Hz at 12 dB per octave)

Electronic Bass Control

preamp- and speaker-level inputs

20' power harness included

dimensions: 28-7/8"W x 7-7/8"H x 14-1/4"D

warranty: 5 years (free repair or replacement for 2 years, prorated replacement for years 3 through 5)

Vehicle-specific enclosures with subs? Say what?

Instead of the usual sub in a box, the manufacturer creates a molded enclosure that fits perfectly into a convenient spot in your specific vehicle, housing a high-quality sub. Some enclosures even include a built-in amp, for the ultimate in stealth bass. The advantages? You don't lose much space (if any), your sub is perfectly matched to its enclosure, and your enclosure has a factory look that won't tell potential thieves you have an awesome sound system. Doesn't get better than that.

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Great Solution

Didn't want something that would blow the windows out, just upgrade the sound. This was an easy install and it sounds great. It does not compare to the dual 12" 800W subs in one of my other cars, but it sounds MUCH better than the Bose system in my wife's 2007 Lexus IS250. Very happy with the product!

Pros:Easy install, great sound for the money

Cons:It stumbles a little on the really deep lows, but you have to crank it up it to even notice!

nice clear bass right out of the box

finding a sub that fits under the backseat of a f-150 super crew is a bit of a challenge if you can't commit the entire back seat space to the sub. I also needed to fit two amps back there so finding a box & integrated sub that only takes up half was exactly what I was looking for. I tried the little Kicker sub box but it couldn't keep up. This box thumps just fine for the amount of space it needs. My only complaint is that the mounting brackets don't fit. They literally are too small to line up with the mounting hole on the box. This is a pricey sub and cheap brackets that don't fit is pretty cheesy. I know that brackets are inexpensive at other retailers but you would expect for this kind of money that there would be a bit more attention to detail. this thing is really expensive for a single 10" but if space is a huge issue like it was for me, then this is a fantastic solution.

Pros:Fits great, does not take the whole back seat space, full, compromised bass for the size of the box.

Cons:expensive for a single 10" sub set up, provided brackets didn't fit.

great bass

this enclosure sounds awesome with the stock head unit. dont be worried about not getting enough bass - the bass hits hard and clean. i was totally blown away, and with the EBC you can increase or decrease the amount of bass easily. thanks to the Crutchfield tech team i was able to install it in about 2 hours. the box fit perfect and the kit came with everything i needed. thanks again Crutchfield - you guys rock!

Pros:pretty easy install. all the hardware was included. fits like a glove.

Cons:wiring diagram would have been nice, but one call to the tech team fixed that.

Great construction, good bass for the money

Written By Geno, Glendale AZ on Friday, June 22, 2012

This loaded sub came with EVERYTHING for the installation. From power wire, fuse, ground, rca line outputs and bass knob. I was unaware of this when I ordered since it really doesn't specify in the highlights section of the web page. It states 20' power harness, but that description is somewhat vague. So I went and purchased a nice 50A AGU fuse Holder, 8 guage wire, crimp-on terminal connectors and a line output converter all for nothing. I did however use the AUG fuse holder and 8 gauge power wire. It's obvious that you should have some experience installing car audio in order to propperly install this sub. However, a generic install guide as to how to incorporate the supplied RCA line inputs into your vehicles factory speakers could help out potential customers interested in this item, if they are not too confident in their skills. For the price, sound, ease of install and aesthetics, it was well worth the price. The bass is tight and clean, and the box looks like it was meant to be there from the factory as it fits perfectly underneath the seat, even with my nice Raptor floormat in the back.

Pros:Tight, clean bass. Easy to install and comes with a bass knob so you can control how much bass you want. It's not going to rattle your teeth, but then again I'm not in highschool anymore and enjoy being able to hear the rest of the musical notes. If you have a 2011 Ford F150 Super Crew, the box only takes up about half of the rear seat and fits perfectly. Someone AKA thief would have to look pretty hard through the windows to notice it if they were shopping from the outside.

Cons:I have a 2011 F150 Raptor Super Crew with the upgraded Sony Sytem and Nav. If you try ordering with this as your vehicle on the website, they don't have the super crew listed and it defaults to the supercab sub which is obviously not the same. I used an 11 platinum to bring up the correct model. Also, I purchased all items needed for an install i.e. power wire, 50A AUG Fuse holder, terminal crims and line output converter since the description was vague. No need, as this product comes complete.

Solid, tight bass

I had to wait 2 weeks for this item to come in so I really got to know and listen to my system without it. Once I bolted it down, the difference was remarkable. The bass is clean and tight and compliments my Infinity speakers to the bone.

Pros:Nice fit under the seat as you have to make sure it is in the right place before you drill as the gas tank is also on the driver's side of the truck. I moved it inward just a couple of inches so it's away from the edge, and it mounted perfectly. It's out of sight sound without in the way speakers or bass tubes.

Cons:You lose the storage space under the seat, but from mounting the amp behind the driver's side rear seat, I lost the ability to raise that seat anyway.

Enclosure: The ThunderForm enclosure is made of molded high-density
polyethylene resin, which dampens resonance and is rigid enough to resist flexing. It
is an acoustic suspension (sealed) chamber.

Mounting Location: This enclosure is designed to mount under
the rear seat on the driver's side. Note:
The provided dimensions are taken at the widest points of the enclosure. Keep in mind
that this enclosure is custom made to fit in this particular vehicle, so the enclosure
will fit properly in only one specific location.

10" Terminator Subwoofer: This enclosure comes loaded
with one 10" MTX Terminator subwoofer. The woofer has an unusual impedance,
specifically designed for the built-in amp, and cannot be replaced with standard
MTX models.

Class D Amplifier: The enclosure contains a built-in 200-watt
Class D (digital) amplifier that allows RCA or speaker-level input. The amplifier
is highly efficient and designed specifically for use with the subwoofers in the
enclosure.

Electronic Bass Control (EBC): The EBC is a wired remote and
allows you to adjust the bass level from anywhere in the vehicle. Installing the
EBC is optional.

Low-pass Crossover: The low-pass crossover point is adjustable
from 50 to 150 Hz for a seamless transition between the output of this unit and that
of the other speakers in the vehicle.

Controls:

Gain Control: rotary control; set
the gain of the amplifier is match the input

Auto Turn-On Feature: When speaker level inputs are used, the
system will automatically turn on and off with the radio.

Note: The auto turn-on feature does not
operate when preamp level inputs are used, connecting the
remote turn-on lead is required.

Warranty

5 Year Warranty Terms: This product carries a 5-Year
Prorated Warranty with the following terms:

Years 1-2: Products found to be defective in materials
or workmanship during the first two years will be, at Mitek's option,
repaired or replaced by Mitek at no charge. The warranty period does not
renew, but continues on from the original date of purchase.

Years 3-5: The purchase price of an item which becomes
defective after the first two years and prior to the end of the warranty
period will be prorated and credited toward the purchase of a new MTX
product. The amount of proration is determined by dividing the original
purchase price by the number of months in the warranty period (60), then
multiplying the result by the number of months remaining in the warranty
period.

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